There are cases when, if you pass a NULL UI_METHOD, the called
function will use an internal default. This is well and good, but
there may be cases when this is undesirable and one would rather send
in a UI that does absolutely nothing (sort of a /dev/null). UI_null()
is the UI_METHOD for this purpose.
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2744)
Provide a callback interface that gives the application the ability
to adjust the nascent SSL object at the earliest stage of ClientHello
processing, immediately after extensions have been collected but
before they have been processed.
This is akin to BoringSSL's "select_certificate_cb" (though it is not
API compatible), and as the name indicates, one major use is to examine
the supplied server name indication and select what certificate to
present to the client. However, it can also be used to make more
sweeping configuration changes to the SSL object according to the
selected server identity and configuration. That may include adjusting
the permitted TLS versions, swapping out the SSL_CTX object (as is
traditionally done in a tlsext_servername_callback), changing the
server's cipher list, and more.
We also wish to allow an early callback to indicate that it needs to perform
additional work asynchronously and resume processing later. To that effect,
refactor the second half of tls_process_client_hello() into a subroutine to be
called at the post-processing stage (including the early callback itself), to
allow the callback to result in remaining in the same work stage for a later
call to succeed. This requires allocating for and storing the CLIENTHELLO_MSG
in the SSL object to be preserved across such calls, but the storage is
reclaimed after ClientHello processing finishes.
Information about the CliehtHello is available to the callback by means of
accessor functions that can only be used from the early callback. This allows
extensions to make use of the existing internal parsing machinery without
exposing structure internals (e.g., of PACKET), so that applications do not
have to write fragile parsing code.
Applications are encouraged to utilize an early callback and not use
a servername_callback, in order to avoid unexpected behavior that
occurs due to the relative order of processing between things like
session resumption and the historical servername callback.
Also tidy up nearby style by removing unnecessary braces around one-line
conditional bodies.
Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2279)
Split off the portions that mutate the SSL object into a separate
function that the state machine calls, so that the public API can
be a pure function. (It still needs the SSL parameter in order
to determine what SSL_METHOD's get_cipher_by_char() routine to use,
though.)
Instead of returning the stack of ciphers (functionality that was
not used internally), require using the output parameter, and add
a separate output parameter for the SCSVs contained in the supplied
octets, if desired. This lets us move to the standard return value
convention. Also make both output stacks optional parameters.
Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2279)
Move ssl_bytes_to_cipher_list() to ssl_lib.c and create a public
wrapper around it. This lets application early callbacks easily get
SSL_CIPHER objects from the raw ciphers bytes without having to
reimplement the parsing code. In particular, they do not need to
know the details of the sslv2 format ClientHello's ciphersuite
specifications.
Document the new public function, including the arguably buggy behavior
of modifying the supplied SSL object. On the face of it, such a function
should be able to be pure, just a direct translation of wire octets to
internal data structures.
Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2279)
We use an int instead. That means SSL_key_update() also should use an int.
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2609)
This also adds documentation for the pre-existing and related
SSL_renegotiate*() functions.
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2609)
The core SipHash supports either 8 or 16-byte output and a configurable
number of rounds.
The default behavior, as added to EVP, is to use 16-byte output and
2,4 rounds, which matches the behavior of most implementations.
There is an EVP_PKEY_CTRL that can control the output size.
Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2216)
Add details of the use of PSS for signature algorithms.
Document SSL_get_peer_signature_nid() and SSL_get_peer_signature_type_nid().
Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2301)
Add Poly1305 as a "signed" digest.
Reviewed-by: Andy Polyakov <appro@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2128)
Enhance find-doc-nits to be better about finding typedefs for
callback functions. Fix all nits it now finds. Added some new
typedef names to ssl.h some of which were documented but did not
exist
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2151)
find-doc-nits warns if you don't give a "what to do flag"
Don't use regexps for section names, just strings: More consistency.
Rename "COMMAND OPTIONS" to OPTIONS.
Fix a couple of other nit-level things.
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2076)
Commit 0cd0a820ab removed this macro
along with many unused function and reason codes; ERR_FATAL_ERROR()
was not used in the tree, but did have external consumers.
Add it back to restore the API compatibility and avoid breaking
applications for no internal benefit.
Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2049)
Verify that the encrypt-then-mac negotiation is handled
correctly. Additionally, when compiled with no-asm, this test ensures
coverage for the constant-time MAC copying code in
ssl3_cbc_copy_mac. The proxy-based CBC padding test covers that as
well but it's nevertheless better to have an explicit handshake test
for mac-then-encrypt.
Reviewed-by: Andy Polyakov <appro@openssl.org>